The Perks of Being a Wallflower explores the themes of coming of age and loss of innocence. These themes go hand in hand since loss of innocence occurs through the process of coming of age. Through coming of age, one gains more knowledge and understanding, and knowledge is the catalyst of loss of innocence. It is the choices that one makes with new knowledge that determines whether one does in fact 'lose their innocence'.
With the help of his friends, Sam, Patrick, Mary Elizabeth, Bob and Brad, Charlie explores a new side of life involving relationships, sexuality, drugs, parties, alcohol and friendship. Charlie matures and learns to be less ignorant and eventually loses his innocence.
Someone, usually in high school, who sees everything, knows everything, but does not say a word. they are not loners. they are introvertive. Wallflowers are phased in, and faded into the background.
[definition from urban dictionary]